Bicycle helmets must be designed to provide proper protection of the cyclist head from trauma injury following accidental impacting fall. They must also be relatively lightweight to avoid fatigue to the cyclist neck. There is thus always an optimum mix to be found between head protection and weight.
Conventional bicycle helmets are typically made of a layer of crushable material such as synthetic resin foam, extending over the wearers head to mitigate the force of an impact and an external shell attached to the layer of crushable material and increasing the impact strength (resistance to impact). It also serves as a structural support for the crushable material.
There is thus a need for a helmet design that provides the desired structural support and impact strength while reducing the overall weight of the helmet.